Triangulated portal frames



Sept. 1, 1970 P. G. BUXTON TRIANGULATED PORTAL FRAMES 2 SheetsSheet 1 Filed March 18, 1968 Sept. 1, 1970 P. cs. BUXTON TRIANGULATED PORTAL FRAMES 2 Sheets-Sheet 2 Filed March 18, 1968 FIG. 3

United States Patent Clfice 3,526,068 Patented Sept. 1, 1970 3,526,068 TRIANGULATED PORTAL FRAMES Peter Godfrey Buxton, Kenley, England, assignor to The British Aluminium Company Limited, London, England, a company of Great Britain Filed Mar. 18, 1968, Ser. No. 713,762 Int. Cl. E04c 3/38; E04b N32 US. CI. 52-86 12 Claims ABSTRACT OF THE DISCLOSURE A portal frame capable of being used in the construction of buildings such as glasshouses, sheds, garages and the like, formed from a pair of uprights each in the form of a sub-portal frame and joined at their upper ends by a crossmember formed from one or more lattice girders of triangular cross-section each formed from three parallel beams interconnected by struts and stays.

This invention relates to improvements in frameworks and is particularly concerned with portal frames having a pair of spaced uprights joined by a crossmember.

It is an object of the present invention to provide an improved portal frame which is capable of being easily constructed from a small number of standard component parts and is capable of being used in the construction and erection of buildings such as glasshouses, sheds, garages and the like.

According to the present invention, a portal frame comprises a pair of uprights each constructed as a sub-portal frame and a crossmember composed of at least one lattice girder of triangular cross-section having three beams interconnected by struts and stays, said beams being preferably parallel for at least the major portion of their lengths.

Preferably, each sub-portal frame has a crossmember composed of two tubular or rod-like elements extending out of the general plane of the sub-portal frame and with advantage inwardly of the main frame and joined at their ends at a junction which is also connected to the junction of two further tubular or rod-like members extending from or adjacent to the foot of the uprights of the subframe, one of the beams of a lattice girder being connected to such junction and the other two beams thereof being connected to the uprights of the sub-frame at or adjacent to the upper ends thereof and, with advantage, at the location where the tubular or rod-like elements of the crossmember of the sub-frame join the uprights thereof.

Desirably, the crossmember of the main portal frame is in the form of two lattice girders arranged as an inverted V and the beams are composed of tubular or rodlike members joined together at the same locations as the struts or stays connected thereto so that only a single connecting element need be employed.

With advantage, the connections are effected by connectors of the Triodetic type such as are described and claimed in British Pats. Nos. 769,616, 826,898 and 973,572.

One embodiment of the invention will now be described by way of example, reference being made to the accompanying drawings in which:

FIG. 1 is a perspective view of a portal frame constructed in accordance with the present invention,

FIG. 2 is an enlarged fragmentary side elevational view of the arrangement illustrated in FIG. 1,

FIG. 3 is an enlarged perspective view showing a connecting element with radiating struts or stays and beams,

FIG. 4 is a transverse section through the connecting element of FIG. 3,

FIG. 5 is an elevatioual view showing the flattened end of a strut or stay, and

FIG. 6 is a section similar to FIG. 3 showing a modification.

The portal frame of this embodiment comprises a pair of uprights indicated generally at 1 and constructed as sub-portal frames and a crossmember composed of two lattice girders indicated generally at 2 arranged as an inverted V. The lattice girders 2 are of triangular crosssection having three beams 3 interconnected by struts and stays 4. The lattice girders 2 in this embodiment are arranged with the apex of the triangular cross-section extending downwardly, although it could if desired be disposed the other way up with the apex pointing upwardly. The beams 3 are each composed of tubular or rod-like members 5 joined together, end-to-end at the same locations as the struts or stays 4 are connected thereto so that only a single connecting element 6 need be employed at such locations as will be described in greater detail below. The two upper beams 3 are connected at intervals by transverse members 7. Adjacent transverse members 7 may be considered as two opposed sides of the base of an inverted pyramid, the other two opposed sides of which are formed by beam-forming members 5. From the four corners of such a base extend downwardly the struts or stays 4 to meet at the apex of the pyramid on the lower beam 3. Each girder 2 may therefore be considered to be composed of a plurality of inverted pyramids disposed side-by-side with their apices interconnected by the lower beam 3.

The connections are advantageously effected by connecting elements of the Triodetic type such as are described and claimed in British Pats. Nos. 769,616, 826,898 and 973,572.

A connecting element 6 suitable for use at the apex of the pyramids is shown in FIGS. 3 and 4. The connecting element 6 illustrated comprises two hubs 8 and 9 axially aligned and formed with a number of angularly spaced and radially disposed keyway slots 10 and 11 respectively. The slots 10 and 11 are staggered with respect to each other so that the upper ends of the slots 10 in the hub 8 are closed by the hub 9 and the lower ends of the slots 11 in the hub 9 are closed by the hub 8. These slots 10 and 11 are corrugated and the ends of the struts or stays 4 and the members 5 are flattened and similarly corrugated for engagement therein. The ends of the struts or stays 4 are also inclined to the general direction of length thereof as can be seen in FIG. 4. The struts or stays 4 are retained in the slots 11 by a tapered washer 12 and the members 5 are retained in the slots 10 by a simple washer 13, the assembly being held together by a bolt 14 and nut 15.

A connecting element 6 suitable for use at a corner of the base of a pyramid is shown in FIG. 6 and is similar in most respects to that illustrated in FIGS. 3 and 4. Like reference numerals are used to denote like parts, in this case, it is inverted and also modified by forming the washer 13 as a bracket to which a transverse member 7 is bolted. This member 7 may be of flattened oval-section as shown and may form the support to which the cladding or framework of the outer wall of the structure is secured.

Although the connecting elements 6 have been described as comprising two hubs, it will be appreciated that only a single hub need be provided with the key-way slots suitably disposed.

The beams 3 of each lattice girder 2 are parallel for the major part of their length. In the arrangement illustrated, however, it can be seen from FIG. 2 that the lowermost beam 3 is inclined out of its general direction of length towards the other two beams 3 at the end where it is attached to a sub-portal frame 1. This is not essential, but is preferred. Each sub-portal frame comprises a pair of spaced upwardly extending tubular or rod-like elements '16 with a crossmember composed of two further tubular or rod-like elements 17 extending out of the plane containing the upwardly extending elements 16 and, in this example, inwardly of the main frame. The inwardly extending elements 16 are joined at their inner ends at a juction provided by a connecting member 6 to which are also connected the one ends of two further tubular or rod-like elemets 18 extending from or adjacent to the foot of the upwardly extending elements 16. The end of the lower beam 3 is connected to the connecting element 6 at the junction of the elements 17 and 18 as are also the two endmost struts or stays 4 and the upper two beams 3 are connected to the upwardly extending elements 16 at or adjacent to the upper ends, and, with advantage at the location where the elements 17 are connected thereto so that a single connecting element 6 may be employed at each such location.

Each sub-portal frame further has a cross-member 7a at its upper end similar to the transverse members 7. It will be seen that at the end of each girder 2 there is in effect a pyramid with the base formed by the endrnost beam forming members of the upper beams 3, the endmost transverse member 7 and the cross-member 7a and with four sides defined by two struts or stays 4 and the elements 17. This pyramid is joined at its apex to the apex of a further pyramid whose sides are defined by the elements 17 and 18 and whose base is defined by the elements 16 the cross-member 7a and the base of the sub-portal frame.

It will also be observed that between the two endmost pyramids of a girder 2 there are provided two additional struts or stays 4a which extend between the upper two beams 3 and the lower beam 3 and which correspond to the struts or stays 4 but do not form part of a pyramid.

These struts or stays 4a provide additional strength for the structure when needed but they may in many cases be omitted.

I claim:

1. A portal frame including a cross-member supported at each end by a sub-portal frame, each said sub-portal frame comprising a first pair of elongate elements disposed in spaced-apart relationship and extending upwardly from base means, a second pair of elongate elements extending upwardly from the base means and connected to each other at their upper ends, and a third pair of elongate elements, each element of the third pair being connected 4 3. A portal frame according to claim 2 in which the beams are parallel for at least the major portion of their lengths.

4. A portal frame according to claim 2 in which one of the beams of the lattice girder is connected to the connected ends of the second and third pairs of elements of a sub-portal frame and the other beams of the girder are connected to respective ones of the first pair of elements of the sub-portal frame at the upper ends thereof.

5. A portal frame according to claim 4 in which the other beams are connected to the first pair of elements of the sub-portal frame at locations where the third pair of elements are connected to the first pair of elements.

6. A portal frame according to claim 2 in which the cross member is composed of two lattice girders arranged as an inverted V.

7. A portal frame according to claim 6 in which the lattice girders have the apex of their triangular section at the bottom thereof.

8. A portal frame according to claim 2 in which the beams are composed of elongate elements joined together by connecting elements.

9. A portal frame according to claim 8 in which the struts and stays are connected to the beams by the connecting elements.

10. A portal frame according to claim 2 in which two of the beams and the struts and stays of the lattice girder are formed into a plurality of pyramids joined at their apices by the other of the beams.

11. A portal frame according to claim 1 in which the third pair of elements of each sub-portal frame extend inwardly of the plane of the first pair of elements of that portal frame.

12. A portal frame according to claim 1 including an elongate element directly connecting the upper ends of the first pair of elements of each sub-portal frame.

References Cited UNITED STATES PATENTS 2,895,753 7/1959 Fentiman 287-18936 X 2,931,467 4/1960 Fentiman 287189.36 2,964,147 12/ 1960 Fentiman 52-655 3,079,681 3/1963 Fentiman 287-18936 X 3,152,819 10/1964 Fentiman 287189.36 X

FOREIGN PATENTS 233,980 5/ 1961 Australia. 594,178 3/1960 Canada.

PRICE C. FAW, 111., Primary Examiner U.S. Cl. X.R. 

